Sgt. William Evans said the woman gave two different versions of what happened -- one, that she was smoking a cigarette and it caught the gasoline on fire; and two, that she was trying to burn a piece of paper, which ignited the gas.

The paper in question was a termination notice she received in the morning from her job at a pharmacy, police said.

The woman had gasoline on her clothing, and the driver of a gas tank truck who was making a delivery knocked her to the ground as people rushed to help her, police said.

“I just heard screaming, a bloodcurdling scream. I don't know if she was saying anything, but I didn't understand her if she did,’ said O’Neill. “They put her on the ground, covered her with blankets and tore her bottom half of clothes off and put the fire out on her.”

"She was very lucky that there were people standing there that were able to knock her to the ground, rip her clothes off of her and beat the fire out,” said Evans.

The 51-year-old Ford City woman was taken to Armstrong County Memorial Hospital in Kittanning and transferred to UPMC Mercy, where she was in critical condition.

Evans said police and the district attorney will review security camera video as they try to determine if the fire was an accident or the result of a deliberate act.

Shop 'n Save workers said they were not permitted to comment to Channel 4 Action News.